Question

If the trace of the matrix: A = $\begin{bmatrix} x - 1 & 0 & 2 & 5 \ 3 & x^{2} - 2 & 4 & 1 \

• 1 & - 2 & x - 3 & 1 \ 2 & 0 & 4 & x^{2} - 6 \end{bmatrix}$ is 0 then x is equal to

• A. (–2, 3)
• B. (2, –3)
• C. (–3, 2)
• D. (3), –2)

Answer 1

Answer: (C)

(–3, 2)

Answer 2

Trace of matrix is defined as $\sum_{i = 1}^{n}a_{ii}$ = 2x² + 2x –12 = 0

⇒ x = –3, 2